CN1079046C - Method for non-resin fluid-assisted injection molding of a resin - Google Patents
Method for non-resin fluid-assisted injection molding of a resin Download PDFInfo
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- CN1079046C CN1079046C CN94195100A CN94195100A CN1079046C CN 1079046 C CN1079046 C CN 1079046C CN 94195100 A CN94195100 A CN 94195100A CN 94195100 A CN94195100 A CN 94195100A CN 1079046 C CN1079046 C CN 1079046C
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- resin
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- fluid
- molten resin
- injection molding
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Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
- B29C45/17—Component parts, details or accessories; Auxiliary operations
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
- B29C45/17—Component parts, details or accessories; Auxiliary operations
- B29C45/1703—Introducing an auxiliary fluid into the mould
- B29C45/174—Applying a pressurised fluid to the outer surface of the injected material inside the mould cavity, e.g. for preventing shrinkage marks
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
- B29C45/17—Component parts, details or accessories; Auxiliary operations
- B29C45/1703—Introducing an auxiliary fluid into the mould
- B29C45/1734—Nozzles therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
- B29C45/17—Component parts, details or accessories; Auxiliary operations
- B29C45/1703—Introducing an auxiliary fluid into the mould
- B29C45/1704—Introducing an auxiliary fluid into the mould the fluid being introduced into the interior of the injected material which is still in a molten state, e.g. for producing hollow articles
- B29C45/1706—Introducing an auxiliary fluid into the mould the fluid being introduced into the interior of the injected material which is still in a molten state, e.g. for producing hollow articles using particular fluids or fluid generating substances
- B29C2045/1707—Introducing an auxiliary fluid into the mould the fluid being introduced into the interior of the injected material which is still in a molten state, e.g. for producing hollow articles using particular fluids or fluid generating substances using a liquid, e.g. water
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2995/00—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds
- B29K2995/0037—Other properties
- B29K2995/0063—Density
Abstract
A method for the non-resin fluid-assisted injection molding of a resin to produce a shaped resin article having an improved surface finish, which comprises effecting an excess filling of a mold cavity of a sealed mold with a molten resin to form a molten resin mass having opposite, first and second surfaces respectively facing opposite inner walls of the mold cavity, wherein the excess filling is performed in a specific excess filling ratio which corresponds to an excess ratio of a resin by an amount corresponding to 30 to 90% of the difference between the volume of the mold cavity and the volume exhibited by the resin in accordance with the shrinkage thereof when the molten resin filled in the mold cavity is cooled to room temperature, and subsequently introducing a pressurized non-resin fluid into the mold cavity on a side of the first surface of the molten resin mass to thereby press the second surface of the molten resin mass against the cavity inner wall remote from the side of the introduction of the non-resin fluid. By the non-resin fluid-assisted injection molding method of the present invention, the occurrence of a sink mark on a front surface of a shaped resin article can be effectively prevented without causing the problem of the occurrence of burrs (flashes).
Description
Background of invention
Invention scope
The present invention relates to the auxiliary injection moulding process of a kind of non-resin fluid.More particularly, the present invention relates to a kind of method with the auxiliary resin injection moulding of non-resin fluid, be used to produce the molding resin goods of high surface finish, wherein the molten resin with specified quantity carries out excessive mold filling to die cavity, be formed with respectively towards the first surface of relative mould intracavity wall and the molten resin body of second surface, subsequently the non-resin fluid of pressurization is sent in the die cavity of first surface side of molten resin body, thereby the second surface of molten resin body is pressed to the mould intracavity wall of introducing side away from the non-resin fluid.With the auxiliary injection moulding process of non-resin fluid of the present invention, can prevent from the front of the resin of finalizing the design, indenture to occur, and the problem of overlap not occur.The injection moulding that non-resin fluid of the present invention is assisted is effective especially to producing such molding resin goods, and there are ledge such as muscle, embossment etc. in the local area of such goods on its front, and the molding resin goods thicken in these parts.
The discussion of correlation technique
As you know, when produce with the molten resin injection moulding big thickness arranged or when the molding resin goods of ledge being arranged in its local area, back side, because molten resin volume contraction in the process of its cooling might indenture occur on the front of molding resin goods.For preventing indenture to occur on the front of molding resin goods, known a kind of like this method wherein when applying injection pressure, is used high pressure usually, and after injection moulding, still keep-ups pressure when the molten resin of injection moulding cools off.(this method is " resin pressurization " hereinafter referred to as.) in this resin pressurization, the injection pressure that applies is generally 500～2000Kgf/cm
2, by resin pressure maximum in the die cavity.
But as disclosed among the Japanese Patent Application Laid-Open SpecificationNo.50-75247, there are some problems in above-mentioned resin pressurization.For example, in two stages, be difficult to exert pressure rightly, wish the effect that reaches so that reach the resin pressurization, so that molded operation usually become pretty troublesome and consuming time.In addition, in the resin pressurization, the molding resin goods of production may form overlap along the die parting line of mould.So it is necessary removing deflashing, therefore unavoidably can produce such problem: in molded operation, must increase workload or step.On the other hand, in the resin pressurization, in order to prevent overlap, when adopting quite low pressure, indenture may occur on the resin of part typing, they are at the cast gate place away from die cavity, promptly in the part that can not reach gratifying resin pressure.
In order to solve these problems of resin pressurization, above-mentioned Japanese Patent Applica-tion Laid-Open Specification No.50-75247 proposes the auxiliary injection moulding of a kind of gas, but wherein use an injection molding that contains fixed die lobe and dynamic model lobe, but the inwall of dynamic model lobe has prominent core rod to fixed die lobe inwall, but is consequently determined the die cavity of spill by fixed die lobe and the dynamic model lobe that core rod is arranged.Core rod has one along the hole that y direction extends, and a lift valve is installed at the top in this hole.In this method, after the resin of fusion injects die cavity, the operation lift valve upwards pushes away the molten resin body, so that between the inner surface of core rod and the spill molten resin body that in female mould cavities, forms, form a space, by lift valve the gas of pressurization is sent into above-mentioned space then, thereby the outer surface of molten resin body is pressed to mould intracavity wall away from core rod.The auxiliary injection moulding of this gas is used for replacing using the two stages pressurization in the above-mentioned resin pressurization by using the gas that pressurizes to prevent indenture, and as mentioned above, back one method may overlap occur with the die parting line along die cavity.In Japanes Patant Application Laid-Open Specifi-cation No.50-75247, the amount of the molten resin that injects is not described.
WO90/06220 (corresponding to US5273707 and EP400135) discloses the auxiliary injection moulding of a kind of gas, wherein with the molten resin injection die cavity of volume less than mold cavity volume, specifically be 90～95% of mold cavity volume, then gas-pressurized sent in the die cavity in the remaining space.But, at the inwall of die cavity (introducing side) with inject between the molten resin of die cavity and may form the gap away from gas.Therefore, gas can be clamp-oned the gap, and indenture is occurred.
Found out that by above-mentioned in the auxiliary injection moulding of traditional gas, introducing in the die cavity for the appearance that prevents overlap and in order to ensure gas-pressurized has certain space, the molten resin that will be equal to or less than mold cavity volume injects die cavity.
WO93/14918 discloses and has used a kind of injection molding that hermetically-sealed construction is arranged, but but wherein not only the space between die parting line between dynamic model lobe and the fixed die lobe but also ejector pin and the ejector pin sliding eye inwall in the dynamic model lobe is all sealed.In addition, this patent points out that also a part of inwall has the weir (as the structure of similar muscle) that ledge forms around die cavity, and it is used for accepting the pressure of gas on inwall, so that air pressure can be applied to the required part of the molten resin of injection effectively, to prevent indenture.
But, the injection molding of hermetically-sealed construction is arranged and be added with the weir though use, can not prevent that also gas-pressurized from clamp-oning a part of die cavity of face side of the molten resin body of injection, and the mould intracavity wall towards it should be pressed in this surface.So, can not reach tight contact between its mould intracavity wall in the surface of above-mentioned molten resin body and the face, make the surface smoothness of the molded resin product of generation can not be satisfactory.In addition, because at mould intracavity wall the weir is arranged, the design flexibility of the moulded products that produce is restricted inevitably.In addition, point out in WO93/14918 that die cavity is filled with molten resin or approaching filling.
Recently, the demand of large-scale moulded products such as automobile component and household appliances shell constantly increases.Can be by carrying out back processing as japanning and plating, producing cost is reduced, so producing has the molded resin product of fabulous surface smoothness to wish, indenture being dropped to degree and the goods that naked eyes can not discover in these goods has fabulous and uniform gloss.
But, as above-mentioned, in traditional injection moulding, when the molded resin product that will produce has local ledge at its back side, when its ledge is thicker, under the condition that the overlap problem do not occur, can not make its front drop to gratifying degree the indenture defective occurring corresponding to local ledge.
Summary of the invention
For above-mentioned reasons, the inventor carries out careful extensively and profoundly research, so that solve the problem that the above-mentioned background technical method is unavoidably followed.
Because the result of above-mentioned research, unexpectedly find, in the method for the auxiliary resin injection moulding of a non-resin fluid, under implantation temperature and pressure condition in preliminary election, by the excessive mold filling of appointment than [corresponding to the excessive ratio of resin, the difference of the resin volume that its amount obtains owing to its contraction during with molten resin cool to room temperature when being contained in die cavity in for mold cavity volume 30～90%], when the die cavity that seals injection molding being carried out excessive mold filling with molten resin, thereby be formed with the molten resin body on relative first and second surfaces, non-resin fluid with pressurization is fed in the die cavity of molten resin body first surface one side then, make the molten resin body press to mould intracavity wall (this mould intracavity wall is sent into side away from the non-resin fluid) towards second surface, can effectively prevent indenture like this, and don't overlap occurs, thereby produce the molded resin product of fabulous surface smoothness.On this newfound basis, finished the present invention.
Therefore, first purpose of the present invention provides a kind of new method with the auxiliary resin injection moulding of non-resin fluid, and this method does not only produce indenture, nor overlap occurs, produces the molded resin product that high surface finish is arranged so this method utmost point is applicable to.
For those skilled in the art, above-mentioned purpose, feature and advantage with other of the present invention will become very clear more in conjunction with the accompanying drawings from following detailed description and attached claim.
Brief description of drawings
In the accompanying drawings:
Fig. 1 is the profile that is used for the sealing injection molding of a kind of form of the present invention;
Fig. 2 (a) and Fig. 2 (b) are respectively the amplification profiles that two kinds of form ejector pins of ejector pin sliding eye are arranged, and ejector pin can slide in the hole, but this knock hole is respectively in the dynamic model lobe;
Fig. 3 is a kind of part sectioned view of the molding resin goods that local ledge is arranged of form.
Fig. 4 is the profile that is used for another kind of form sealing injection molding of the present invention;
Fig. 5 is a kind of amplification profile of the ejector pin that the non-resin fluid passage is wherein arranged of form, but part dynamic model lobe and part ejector pin support plate are shown;
Fig. 6 is illustrated in to inject before the fusion form resin, and how heating surface is to the diagram of the mould intracavity wall of molten resin body second surface;
Fig. 7 (a) is a kind of plan view of molded resin product of form;
Fig. 7 (b) is the profile of Fig. 7 (a) along the VII-VII line;
Fig. 8 is the surface smoothness state diagram of the molded resin product that makes of embodiment 3, and wherein excessive mold filling ratio is 57%;
Fig. 9 is the surface smoothness state diagram of the molded resin product that makes of comparative example 3, and wherein excessive mold filling ratio is 0; And
Figure 10 is the surface smoothness state diagram of the moulded products that makes in the Comparative Examples 8, wherein adopts the resin pressurization.
In Fig. 1 to Figure 10, parts that identical numeral is identical with letter representation and part.
Detailed description of the invention
According to the present invention, provide a kind of with the auxiliary resin injection moulding process of non-resin fluid, with production the molded resin product of high surface finish is arranged, this method comprises:
(1) make one have the fixed die lobe and with the injection molding of the supporting But moving die lobe of fixed die lobe, thereby provide one by the inwall of fixed die lobe and the definite die cavity of inwall of But moving die lobe, die cavity communicates with resin inlet and non-resin fluid inlet, and injection molding is sealed to be spilt from mould when the non-resin fluid is sent into die cavity preventing;
(2) under the implantation temperature and pressure condition of preliminary election, by the die cavity of resin inlet with the resin injection injection molding of melting form, it measures W2Represent with following formula (I): W2(gram)=W1(gram)+Wx(gram) (I) in the formula, W1By formula W1＝ρ·V
1Determine, wherein resin density (the g/cm of ρ under normal temperature, normal pressure, measuring3)，V
1By formula V1＝V
0(1-X) determine, wherein V0Be mold cavity volume (cm3), X is the cubical contraction of resin, cubical contraction is by formula
Determine, wherein VaFor under the implantation temperature and pressure of preliminary election, the volume (cm of the melting form resin of predetermined weight3)，V
bVolume (cm for the solid form resin of predetermined weight when the cool to room temperature3); And
Wx is determined by formula (II): Wx＝ρ·γ·(V
0-V
1) (II) in the formula, ρ is as above regulation, Y is 0.3～0.9, V0And V1For what as above stipulate, therefore with molten resin die cavity is carried out excessive mold filling, be formed with towards the first and second apparent surfaces' of relative mould intracavity wall molten resin body; And
(3) will be in the die cavity of the non-resin fluid of the pressurization of the inertia first surface side of sending into the molten resin body to resin, thereby second face of molten resin body will be pressed to mould intracavity wall towards described second surface.
Hereinafter, will explain the inventive method referring to figs. 1 to Figure 10.
In the step (1) of the inventive method, make a kind of injection molding.This injection molding is made by metal material such as steel usually.
Fig. 1 represents a kind of injection molding of the present invention that is used for.As shown in Figure 1, but the injection molding 1 that is used for the inventive method comprise fixed die lobe 1a and with the supporting dynamic model lobe of fixed die lobe 1a, thereby but obtain the die cavity 2 that the inwall 2b by the inwall 2a of fixed die lobe 1a and dynamic model lobe 1b determines.Die cavity 2 communicates with resin inlet (the notes road 4a of sprue bushing 4) and non-resin fluid inlet.Injection molding 1 usefulness water-tight equipment 3a～3e sealing spills from injection molding 1 when the non-resin fluid is sent into die cavity 2 preventing.Each water-tight equipment 3a～3e can be O type rubber ring.With regard to injection molding 1, but at dynamic model lobe 1b away from die cavity 2 one sides, closed chamber 7 is arranged, but it is determined by the inwall of the outer wall of dynamic model lobe 1b, spacer block 8 and the inwall of base plate 9.Closed chamber 7 is equipped with ejector pin support plate 6 and many ejector pins 5, but each ejector pin reliably is connected to the ejector pin support plate 6 (as shown in Figure 1) on dynamic model lobe 1b one side, but dynamic model lobe 1b has many ejector pin sliding eye 5a, wherein many slidably ejector pins 5 can be installed respectively.Ejector pin support plate 6 is by for example making with bolt and the interconnective two boards of nut.Each ejector pin 5 passes ejector pin sliding eye 5a, extends between die cavity 2 and closed chamber 7, so that produce a non-resin fluid passage between around the inwall of each ejector pin slide opening 5a and each ejector pin 5 longitudinal extensions, and each ejector pin 5 has the front end that is exposed to die cavity 2.The opposite side that ejector pin support plate 6 is connected to the side that many ejector pins 5 are arranged relatively reliably is used to promote the rod 10 that ejector pin support plate 6 promotes.
But there is a perforate end non-resin fluid passage in the inwall 2b of dynamic model lobe 1b, this perforate end is as the non-resin fluid inlet.
Closed chamber 7 is by non-resin fluid passage and close the communicating of die cavity 2 liquid, and through port 11 communicates with the non-resin fluid source (not shown) of pressurization.Die cavity 2 is sent into and discharged to through port 11, closed chamber 7 and the non-resin fluid passage non-resin fluid that will pressurize.
The rod 10 that is used to promote ejector pin support plate 6 can move back and forth.After in die cavity 2, making molded resin product, but its inwall 2b is separated with fixed die lobe 1a with the dynamic model lobe 1b of molded resin product, injection molding 1 is opened.Subsequently, but mover bar 10 makes ejector pin support plate 6 push dynamic model lobe 1b to, and therefore the front end of the many ejector pins 5 that link to each other with ejector pin support plate 6 is outwards outstanding from ejector pin sliding eye 5a, thereby but ejects molded resin product from dynamic model lobe 1b.
More particularly, the injection molding 1 that uses in the methods of the invention be can step (2) be injected into the molten resin cooling curing during this period of time in the injection molding of maintenance fluid sealing state.In the present invention, term " fluid sealing state " refers to can send into and discharge die cavity 2 by the non-resin fluid inlet except pressurization non-resin fluid, the state that any fluid all can not spill from injection molding 1.
In the injection molding 1 of Fig. 1,, water-tight equipment 3a～3e is housed as shown in Figure 1 in order to reach the injection molding sealing.But water-tight equipment 3a is used for the die parting line between sealing and fixing mould lobe 1a and the dynamic model lobe 1b.Water-tight equipment 3b is used for the interface between sealing and fixing mould lobe 1a and the sprue bushing 4.But water-tight equipment 3c is used to seal the interface between dynamic model lobe 1b and the spacer block 8.Water-tight equipment 3d is used to seal the interface between spacer block 8 and the base plate 9.Water-tight equipment 3e is used to seal the interface between ejector pin support plate 6 and the base plate 9.
With regard to the notes film 1 of Fig. 1, but because pressurization non-resin fluid is sent into die cavity 2 from dynamic model lobe 1b side, thereby the second surface of molten resin is pressed to the inwall 2a of fixed die lobe 1a, therefore, can save the water-tight equipment 3b of fixed die lobe 1a side.
In the step (2) of the inventive method, under the implantation temperature and pressure condition of preliminary election, by the die cavity 2 of resin inlet (annotating road 4a) with the resin injection injection molding 1 of fusion form, its consumption (W
2) use formula W
2(g)=W
1(g)+Wx (g) expression, wherein W
2, W
1With Wx is as above to stipulate, thereby with molten resin die cavity 2 is carried out excessive mold filling effectively, so that the relative first surface of the molten resin body that generates and tight respectively inwall 2b, the 2a that faces die cavity 2 of second surface.
In the step (3) of the inventive method, pressurization non-resin fluid is sent in the die cavity 2 of molten resin body first surface side, thereby made the second surface of molten resin body press to mould intracavity wall 2a towards second surface.
In the auxiliary injection moulding of traditional gas, in order to attempt to solve the problem that the resin pressurization produces, promptly in the resin pressurization, the problem of overlap occurs along die parting line, die cavity is carried out excessive mold filling without molten resin for what increase that resin pressure carries out that excessive mold filling causes.
But the feature of a maximum of the inventive method is to compare die cavity with molten resin by the mold filling of appointment to carry out excessive mold filling.Why die cavity can be with the reason of the excessive mold filling of molten resin, the effect compression of the injection molding pressure that molten resin can be applied continuously.
Why the excessive injection (being the excessive mold filling of die cavity) of molten resin is that effective reason is as follows.When the non-resin fluid of pressurization when the first surface side of molten resin body is sent into the die cavity of excessive mold filling, make the complete unlikely inflow of non-resin fluid of pressurization and clamp-on in the part die cavity of the second surface side of molten resin body.So the whole area of molten resin body second surface can closely be pressed to the mould intracavity wall towards second surface in die cavity, consequently produce the molded resin product of high surface finish.
Those skilled in the art may think, after excessive molten resin injects die cavity, can leaving space in die cavity, even consequently in step (3), attempt the non-resin fluid of pressurization is sent into the die cavity of molten resin body first surface side, also be difficult to send into the non-resin fluid, perhaps the pressure of Jia Ya non-resin fluid only can act on the limited position of molten resin body first surface.Therefore, those skilled in the art may think that it can not closely press to the whole area of molten resin body second surface the mould intracavity wall towards second surface.
But, beyond thoughtly be, the inventor finds surprisingly, as long as the degree of excessive mold filling is in the scope of appointment of the present invention, above-mentioned this problem can not appear in the step (3) of the inventive method, find also that simultaneously the whole area that the pressurization non-resin fluid of sending into the die cavity of molten resin body first surface side successfully is used for making molten resin body second surface is pressed to mould intracavity wall towards second surface equably with gratifying power.In addition, though it is known usually, the molten resin quantity that is injected into die cavity is many more, overlap may appear more, but the inventor finds first, promptly use molten resin that die cavity is carried out excessive mold filling, as long as the degree of excessive mold filling in the scope of appointment of the present invention, just can prevent the appearance of overlap well by using sealed mould.
As mentioned above, in the step (2) of the inventive method, under the implantation temperature and pressure condition of preliminary election, by the resin injection die cavity of resin inlet with the fusion form, its consumption (W
2) represent with following formula (I):
W
2(g)＝W
1(g)+Wx(g) (I)。
In formula (I), W
1(g) be illustrated under the implantation temperature and pressure of preliminary election the molten resin weight of (the inexcessive mold filling) die cavity of under not compressed condition, packing into.In formula (I), molten resin amount [W is injected in Wx (g) expression
2(g)] excessive part.W
1For example available laxative remedy is determined.At first, under the implantation temperature and pressure condition of preliminary election, the fusion form resin of lower weight is injected die cavity by resin inlet, injection moulding subsequently, thus confirm the molten resin that injects underfill die cavity still.(with regard to suitable implantation temperature and pressure condition, when resin was polystyrene, temperature was generally 190～250 ℃, and pressure is generally 500～2000kgf/cm
2) repeat injection moulding, increase weight resin simultaneously step by step, until till can confirming that the molten resin that injects is full of die cavity and don't is compressed.The resin that records so heavily can be used as the W of formula (I)
1As mentioned above, determine Wx (g) with formula (II):
Wx=ρ Y (V
0-V
1) (II) in the formula, ρ is an as above regulation, Y is 0.3～0.9, V
0And V
1For what as above stipulate.In formula (II), Y is excessive mold filling ratio.When Y represented with percetage by weight, excessive mold filling ratio of the present invention was 30～90%.Excessive mold filling ratio is preferably 50～80%.
When excessive mold filling than less than 30% the time, the pressurization non-resin fluid of sending into may be got in a part of die cavity of molten resin body second surface side, so that the non-resin fluid of pressurization is fully pressed to the whole area of molten resin body second surface the mould intracavity wall towards second surface unsatisfactorily, so molded resin product is difficult to obtain uniform high surface finish.On the other hand, when excessive mold filling than greater than 90% the time, overlap may occur.In order to remove deflashing, need time-consuming polishing step.In addition, when excessive mold filling ratio surpasses 90%, exist to make the impaired danger of mould.In addition, because to the local excessive propelling of the second surface of molten resin body, the uniformity of molded resin product surface smoothness is damaged towards the mould intracavity wall malformation of molten resin body second surface.But when excessive mold filling ratio is 30～90%, particularly 50～80% o'clock, the appearance of indenture unexpectedly can drop to the careless degree of naked eyes, and don't overlap is occurred and surface smoothness inhomogeneous.With regard to being used for resin of the present invention, have no particular limits.The resin that is used for the inventive method can be selected from those resins that are generally used for traditional injection moulding and extrusion molding.The resin that can be used for the inventive method comprises thermoplastic resin, as polystyrene, acrylonitrile/butadiene/styrene ter-polymer resin, acrylonitrile/styrene copolymer resin, methacrylate resin, acetal resin, polyethylene, polyamide, Merlon, Noryl and polyphenylene sulfide; And thermosetting resin.Be used for resin of the present invention and can contain all kinds conventional additives, as plasticizer, stabilizing agent, ultra-violet absorber, colouring agent, releasing agent; Fiber enhancer is as glass fibre and carbon fiber; And various fillers, as glass marble, calcium carbonate and talcum.The quantity of the spendable quantity of these additives in background technology, using usually.
Hereinafter, will describe the step (3) of the inventive method in detail, promptly Jia Ya non-resin fluid sends into.
Now referring to Fig. 1, after step (2) is finished, will be that the pressurization non-resin fluid of inertia is sent in the die cavity 2 of molten resin body first surface side, thereby the second surface of molten resin body will be pressed to mould intracavity wall 2a towards second surface resin.Step (3) can be carried out after step (2) immediately.On the other hand, can there be reasonable time at interval between step (2) and the step (3), as long as step (3) was carried out before the molten resin body solidifies.
Under the situation of injection molding 1, when the non-resin fluid of pressurization was provided by non-resin fluid source (not shown), the non-resin fluid of pressurization entered closed chamber 7 from non-resin fluid bore 11 in Fig. 1.
The example that can be used for non-resin fluid of the present invention comprises and at room temperature is the material of gaseous state, as nitrogen, air, carbon dioxide and argon gas; And be the material of liquid at room temperature, as water.Inert gas such as nitrogen are preferred.The suitable pressure of non-resin fluid of pressurization is relevant with many factors, as the shape and the size of used resinous type and the moulded products that will produce.But the pressure of non-resin fluid is generally 5～100kgf/cm
2G.
By increasing the pressure of non-resin fluid in closed chamber 7 of pressurization, the pressurization non-resin fluid in closed chamber 7 is sent into die cavity 2 by forming the non-resin fluid passage between around the inwall in each ejector pin sliding eye 5a and each ejector pin 5 longitudinal extensions.More particularly, the non-resin fluid of pressurization is sent into towards the die cavity 2 of the first surface side of the molten resin body of mould intracavity wall 2b.Therefore, the second surface of molten resin body is pressed towards the mould intracavity wall 2a towards second surface.Therefore, when molten resin body cooling curing, can make the moulded products of high surface finish, the goods that the goods of fabulous gloss promptly arranged and fabulous mould intracavity wall 2a structure repeatability is arranged, it does not have indenture.
Usually, but between the inwall of ejector pin 5 and the ejector pin sliding eye 5a that in dynamic model lobe 1b, forms, must form a space, so that the non-resin fluid can flow by this space free.So, do not need the space that provides other in principle.But, making shape shown in Fig. 2 (a) and 2 (b) into by being generally circular ejector pin 5, the non-resin fluid that can be pressurization enters the space that provides wideer more reposefully.
No matter under which kind of situation, but the space between the inwall of the ejector pin sliding eye 5a that all requires not make molten resin clamp-on ejector pin 5 and dynamic model lobe 1b, and only allow the non-resin fluid of pressurization to flow by it reposefully.
But send into dispensable from dynamic model lobe 1b side the non-resin fluid of pressurization.If desired, the non-resin fluid of pressurization can be sent into from fixed die lobe 1a side.But in this case, it is necessary that suitable non-resin fluid supply route is arranged in fixed die lobe 1a.For example, non-resin fluid supply route (the similar route that is made of aperture 13, level and vertical non-resin fluid passage 12 and 12a shown in Figure 4 is arranged) can be arranged by this way, so that the non-resin fluid is opened import department to die cavity 2 in the mould intracavity wall 2a of fixed die lobe 1a in fixed die lobe 1a.
As mentioned above, in a preferred embodiment of the invention, the non-resin fluid of pressurization is sent in the die cavity of first surface side of molten resin body, thereby the second surface of molten resin body is pressed to mould intracavity wall towards second surface, so that high surface smoothness is arranged corresponding to the surface of the molded resin product of molten resin body second surface.So first and second surfaces of molten resin body correspond respectively to the back side and the front of molded resin product.
After the non-resin fluid injection with pressurization, with the molten resin cooling curing in the die cavity 2.After this, from die cavity 2, discharge the non-resin fluid of pressurization.Then open injection molding 1, but from dynamic model lobe 1b, eject molded resin product.
Method of the present invention is specially adapted to produce the molded resin product in that local ledge is arranged corresponding to molten resin body first surface side, and molded resin product has bigger thickness (being ledge, as muscle, embossment and combination) at ledge.Specifically, it is effective especially that method of the present invention is used to produce such special-shaped product, and the width (representing with alphabetical w among Fig. 3) of wall thickness in these goods (representing with alphabetical t among Fig. 3), local ledge and the height (representing with alphabetical h among Fig. 3) of local ledge have following relation:
And
。
When satisfying the molded resin product of last two formulas with traditional injection moulding production, a part of planar side at molded resin product has indenture probably, this part is corresponding to the opposition side part relevant with local ledge, and molded resin product has bigger thickness (the above-mentioned part of planar side abbreviates " thickening " hereinafter as) in this section.In addition, in this case, the thickening of molded resin product can not obtain uniform gloss.
Fig. 4 is the sectional drawing that can be used for the injection molding of another form sealing of the present invention.
The injection molding of Fig. 4 is similar to but has some to have any different with the injection molding of Fig. 1.But being the dynamic model lobe 1b of injection molding 1, a difference between these two kinds of injection moldings wherein have another non-resin fluid to send into the route of die cavity 2, as representing among Fig. 4 with pressurization.This other route is made of aperture 13, horizontal-extending passage 12 and the vertical passage 12a that extends.With regard to this another route, the non-resin fluid of the pressurization that will be provided by the fluid source (not shown) by aperture 13 and level and vertical non-resin fluid passage 12 and 12a is sent into die cavity 2.But vertically extending non-resin fluid passage 12a has an openend in the inwall 2b of dynamic model lobe 1b, and openend is as second import of non-resin fluid.The open upper end of vertical non-resin fluid passage 12a has metal polyporous material 14 suitably to insert wherein.Require metal polyporous material 14 not allow the resin of fusion clamp-on wherein, but allow the non-resin fluid of pressurization to flow through reposefully.Metal polyporous material 14 is for example preferably made by the particle stainless steel of sintering.Second import of non-resin fluid communicates with the non-resin fluid source, and this fluid source can be identical or different with another fluid source, and another fluid source communicates with another non-resin fluid inlet (first import) of the perforate upper end that is in ejector pin sliding eye 5a.
Another difference between the injection molding 1 of Fig. 1 and the injection molding 1 of Fig. 4 is that the injection molding 1 of Fig. 4 has central plate 15 and water-tight equipment 3f.But water-tight equipment 3f is used for the interface between center seal plate 15 and the dynamic model lobe 1b.Central plate 15 is applicable to level and vertical non-resin fluid passage (not shown), can be in central plate 15, the non-resin fluid passage of level links to each other with the 12a fluid sealing of vertical non-resin fluid passage and there is the aperture (not shown) that communicates with non-resin fluid source (not shown) the non-resin fluid passage of level.Under these circumstances, the non-resin fluid passage 12 of aperture 13 and level can be saved.
Under the situation of injection molding shown in Figure 41, closed chamber 7 can save, if each ejector pin 5 of the inwall of each ejector pin sliding eye 5a and longitudinal extension around between the space sealed satisfactorily.But, be difficult to make above-mentioned space sealing usually, and simultaneously ejector pin 5 slided in ejector pin sliding eye 5a.So, even when the non-resin fluid of pressurization is only sent into by aperture 13 and level and vertical non-resin fluid passage 12 and 12a, still preferably have closed chamber 7.When the number of ejector pin 5 quite after a little while, preferably introduce the non-resin fluid of pressurization by two routes, the route that closed chamber 7 promptly arranged with level and vertical non-resin fluid passage 12 and the route of 12a are arranged.
In the injection molding 1 of Fig. 4, available solid metal fragment (not shown) replaces above-mentioned metal polyporous material 14, as long as the suitable space that has between around the inwall of vertical non-resin fluid passage 12a and the vertically extending such solid metal fragment non-resin fluid of the pressurization of making to flow.The solid metal fragment for example can have the section of the ejector pin 5 of two kinds of forms shown in similar Fig. 2 (a) and 2 (b).If desired, the solid metal fragment can extend along the whole length of vertical non-resin fluid passage 12a.
Fig. 5 is the vertical section enlarged drawing that another form ejector pin 5 of non-resin fluid passage is wherein arranged, but part dynamic model lobe 1b and part ejector pin support plate 6 are arranged.As shown in Figure 5, ejector pin 5 can be designed to the hollow structure as non-resin fluid passage 12a, and metal polyporous material 14 suitably is inserted in the perforate end of die cavity 2 one sides.In this case, non-resin fluid passage 12 is installed in the ejector pin support plate 6 as shown in Figure 5.The non-resin fluid of the pressurization that provides by the horizontal non-resin fluid passages 12 in the ejector pin support plate 6 flows into die cavity 2 by the vertical non-resin fluid passage 12a that forms in ejector pin 5.
In the method for the invention,, preferably on mould intracavity wall 2a, insulation material layer is housed, so that the second surface of molten resin body is pressed to the inwall 2a of die cavity by the insulation material layer on it when injection molding is made by metal material.With this preferred mode of the inventive method, can obviously improve the gloss intensity and the uniformity in the front (comprising reinforcement) of molded resin product.The reason of this beneficial effect is to play the second surface effect of cooling rapidly when contacting with mould intracavity wall 2a that prevents the molten resin body at the insulation material layer of installing on the mould intracavity wall 2a, so that when under the pressure of the pressurization non-resin fluid of sending into, the second surface of molten resin body being pressed to mould intracavity wall 2a, the good fluidity of the second surface of molten resin body can not lost rapidly, and therefore the non-resin fluid of pressurization can obviously improve the effect of exerting pressure of second surface.
Above-mentioned insulation material layer is that the heat-insulating material of 60～0.06w/mk is made by thermal conductivity factor preferably.The example of representative heat-insulating material comprises polyimides, epoxy resin, phenolic resins, polytetrafluoroethylene (PTFE) and pottery.The suitable thickness of insulation material layer is relevant with the type of heat-insulating material, but preferred 10～500 μ m, more preferably 30～200 μ m.
On the other hand, in the present invention, can preferably in step (2), inject molten resin towards the mould intracavity wall 2a of molten resin body second surface and heat in the past.This other method of preheating by relating to mould intracavity wall 2a can obtain resembling with above-mentioned and relates to the identical good result that the optimal way that uses insulation material layer reaches.Heated mould cavity wall 2a for example can be undertaken by the inductance coil that covers with electrically insulating material before injecting in step (2).
Fig. 6 is the diagram how presentation surface heats before the resin injection of mould intracavity wall in the fusion form of molten resin body second surface.As shown in Figure 6, inductance coil 16 closely contacts with mould intracavity wall 2a, and mould intracavity wall 2a is carried out the inductance heating.Because inductance coil 16 alternatives are heated mould cavity wall 2a only, but rather than heat whole dynamic model lobe 1a, the cooling of molten resin body can be carried out effectively after injection.
Preferably, the above-mentioned heating-up temperature before mould intracavity wall 2a injects in step (2) equals or more is higher than such temperature, under this temperature, the elastic modelling quantity of resin be lower than resin at room temperature elastic modelling quantity 1/3.
Heating with 16 couples of mould intracavity wall 2a of inductance coil also can be by carrying out with above-mentioned different mode.For example, inductance coil 16 can be embedded among the fixed die lobe 1a, is used for just below mould intracavity wall 2a to be heated.Use this inductance coil of imbedding 16, but can inject before the resin can be in dynamic model lobe 1a heated mould cavity wall 2a.But, might only heat a part of mould intracavity wall 2a corresponding to the molded resin product thickening that will produce by using inductance coil 16 to be embedded in mode in the dynamic model lobe 1a.
Implement best mode of the present invention
Reference example is illustrated in greater detail the present invention, and these embodiment are not as limitation of the present invention.
Embodiment 1
Use the sealing injection molding of steel, produce molded resin product as shown in Figure 7, and estimate the surface smoothness state of molded resin product.The sealing injection molding that uses has identical as shown in Figure 1 structure, and different is that used injection molding does not have water-tight equipment 3b.Mold cavity volume is 202cm
3
Molded resin product has following size characteristic: wide (representing with the alphabetical A among Fig. 7 (a)) is 200mm, long (representing with letter b among Fig. 7 (a)) is 300mm, high (representing with the letter C among Fig. 7 (a)) is 40mm, and wall thickness (representing with alphabetical D among Fig. 7 (a)) is 2.5mm.Moulded products has wide (letter e is represented in Fig. 7 (a)) to be the muscle of 10mm for 6mm with height at its back side.
Details are as follows for production stage among the embodiment 1:
The condition of injection moulding is as follows: resin: the Asahi Chemical Polystyrene (trade name of high impact polystyrene, by Asahi Kasei Kogyo Kabushiki Kaisha, Japan produce and market, proportion are 1.05, measure under normal temperature, normal pressure) volume of die cavity: 202cm
3Barrel temperature: 230 ℃ of injection molding temperature: 45 ℃ of injection pressure: 50kg/cm
2Resin pressure: 500kg/cm in (gauge pressure of injection machine) die cavity
2The non-resin fluid of (maximum) pressurization: N
2The pressure of the non-resin fluid of pressurization: 40kg/cm
2(gauge pressure) cool time (having annotated the time that begins to measure): 50 seconds from resin
In embodiment 1, the W in the formula (I)
1, Wx and W
2As follows: W
1: 200gWx:6gW
2: 206g
In embodiment 1, the Y in the formula (II) is 0.43, so excessive mold filling ratio is 43%.
Injection moulding is carried out as follows:
High impact polystyrene is packed in the barrel of injection machine by hopper, heating cylinder (barrel temperature: 230 ℃) then, thus obtain molten resin, then with 206g molten resin (excessive mold filling ratio: 43%) use 50kg/cm
2(gauge pressure) injection pressure injects die cavity (volume: 203cm
3Injection molding temperature: 45 ℃).After molten resin has been annotated, the pressurized nitrogen (gauge pressure: 40kg/cm that provides by source of the gas (pressure bottle)
2) inwall by import 11, closed chamber 7 and each ejector pin slide opening 5a and each ejector pin 5 of longitudinal extension around between the non-resin fluid passage that forms send into die cavity 2 immediately.Specifically, the gas valve of pressure bottle was opened 5 seconds, then valve-off.After gas valve was closed, pressurized nitrogen kept in die cavity 20 seconds, discharged from die cavity then.From having injected, molten resin cooled off in die cavity 50 seconds, thereby molten resin is solidified.Subsequently, but dynamic model lobe 1b and fixed die lobe 1a are separated, open injection molding.Move and promote rod 10 promotion ejector pin support plates, but so that from dynamic model lobe 1b, eject moulded products with ejector pin.Whether the naked-eye observation molded resin product, checking along the die parting line of injection molding has overlap to exist.Subsequently, allow moulded products under normal temperature, normal pressure, place 3 days.Use the front (corresponding to the second surface of molten resin body) of surface roughness tester (SURFTEST.500, Mitutoyo Corporation, the Japan produce and market) test molded resin product whether to have indenture to occur then.Promptly measure molded resin product just in the face of the displacement of its vertical direction, and as the degree of depth (μ m) of indenture.A part is carried out displacement measurement with respect near the front [representing as the dotted line that arrow is arranged] the axle that forms muscle on the back side in Fig. 7 (b).The result lists table 1 in.
Embodiment 2～6
Repeat basically the step identical with embodiment 1, different is by changing excessive mold filling than changing the weight resin of wanting injection moulding, as shown in table 1.The result lists table 1 in.The surface smoothness state of the molded resin product that obtains in embodiment 3 is shown in Fig. 8.
Comparative Examples 1～7
Repeat basically the step identical with embodiment 1, different is by changing excessive mold filling than changing the weight resin of wanting injection moulding.The result lists table 1 in.The surface smoothness state of the molded resin product that obtains in Comparative Examples 3 is shown in Fig. 9.
As finding out from table 1, in embodiment 1～6, its excessive mold filling is than in 30～90% scopes, and displacement (degree of depth of indenture) is low to 5～55 μ m, shows with the naked eye to observe indenture.In embodiment 1～6, also can find out, not observe and overlap occurs.
As also finding out from table 1, in Comparative Examples 1～6, its excessive mold filling is than less than 30%, the degree of depth of indenture greatly to 70 μ m to greater than 1000 μ m, show with the naked eye to be clear that indenture.In addition, in Comparative Examples 7, its excessive mold filling ratio is 93%, observes overlap to occur.
Comparative Examples 8
(resin pressurization)
Use following step, carry out injection moulding, produce molded resin product shown in Figure 7 with the resin pressurization.In this experiment, use unencapsulated injection molding, it has the identical structure of Fig. 1 injection molding, and different is not have water-tight equipment 3a and 3b.With regard to the pressure of molten resin in used resinous type, barrel temperature, injection molding temperature, injection pressure and the die cavity, use with embodiment 1 in identical condition.
With the resin barrel of packing into, and heating obtains molten resin.With the mode identical the 210g molten resin is injected die cavity with embodiment 1.After the injection, secondary pressure described below is applied to last 10 second of molten resin in the die cavity.Secondary pressure: 50Kg/cm
2(gauge pressure of injection machine), it is about 400Kg/cm corresponding to resin pressure
2
Molten resin is opened injection molding after solidifying, and takes out the molded resin product that obtains from die cavity.With regard to the resin of moulding, use the method identical to estimate the appearance of overlap and indenture with embodiment 1.The result lists table 1 in.The surface smoothness state of the molded resin product that Comparative Examples 8 obtains is shown in Figure 10.
Comparative Examples 9
Repeat basically the step identical with Comparative Examples 8, different is that the weight resin that will inject changes over 211g.The result lists table 1 in.
Just as shown in table 1, in Comparative Examples 8, selected best injecting condition for preventing overlap, the indenture degree of depth of its molded resin product reaches 75 μ m, shows to be easy to the naked eye observe indenture.In Comparative Examples 9, the degree of depth of indenture reaches 75 μ m, also observes in addition overlap to occur.
Embodiment 7
Repeat basically the step identical with embodiment 3, different is that insulation material layer is contained on the mould intracavity wall 2a, so that the second surface of molten resin body is pressed to mould intracavity wall 2a by the heat insulation layer material on the mould intracavity wall 2a.As an example, the Kapton that can use thick 50 μ m is as insulation material layer, and available adhesive tape adheres to this film in the face of on the mould intracavity wall 2a corresponding to the molten resin body second surface of the front of the molded resin product that will produce.
With regard to the front of the molded resin product that makes, estimated the degree and the uniformity of gloss.
With glossometer (Digital Variable Gloss Meter, Suga Test InstrumentCo., Japan produce and market).The Evaluation for Uniformity standard of gloss is as follows.*: it is very inhomogeneous and/or observe tangible current mark △ to observe gloss: it is inhomogeneous a bit and/or observed current mark zero to observe gloss: observing the whole front of molded resin product has uniform gloss, and does not observe current mark.
The result lists table 2 in.
Reference example
With regard to the molded resin product that makes at embodiment 3, estimated the degree and the uniformity of gloss with method identical among the embodiment 7.The result lists table 2 in.
Comparative Examples 10
With regard to the molded resin product that makes in the Comparative Examples 8, estimated the degree and the uniformity of gloss with method identical among the embodiment 7.The result lists table 2 in.
Embodiment 8
Repeat basically the step identical with embodiment 3, different is before step (2) is injected will heat towards the mould intracavity wall 2a of the second surface of molten resin body.With the inductance coil heated mould cavity wall 2a that is coated with electrically insulating material.As shown in Figure 6, inductance coil closely contacts with mould intracavity wall 2a, carries out the inductance heating of mould intracavity wall 2a.After mould intracavity wall 2a is heated to about 120 ℃, take down inductance coil, inject molten resin immediately.
With regard to the front of the molded resin product that makes, estimate the degree and the uniformity of gloss with embodiment 7 identical methods.The result lists table 2 in.
As what can find out from table 2, when insulation material layer is contained in mould intracavity wall 2a (as embodiment 7) towards molten resin body second surface, or when step (2) was injected preceding heating surface to the mould intracavity wall 2a of molten resin body second surface (as embodiment 8), the degree and the uniformity of gloss were obviously improved.
Table 1
Annotate: than by ascending expression, arrange embodiment 1-6 and Comparative Examples 1-7 by excessive mold filling.
| Inject amount of resin (g) | Wx (g) | Excessive mold filling is than (%) | The indenture degree of depth (μ m) | Overlap appears | |
| Comparative Examples 1 | 196 | - | - | ≥1000 | Not |
| Comparative Examples 2 | 198 | - | - | ≥1000 | Not |
| Comparative Examples 3 | 200 | 0 | 0 | ≥1000 | Not |
| Comparative Examples 4 | 201 | 1 | 7 | 200 | Not |
| Comparative Examples 5 | 202 | 2 | 14 | 82 | Not |
| Comparative Examples 6 | 204 | 4 | 29 | 70 | Not |
| Embodiment 1 | 206 | 6 | 43 | 55 | Not |
| Embodiment 2 | 207 | 7 | 50 | 18 | Not |
| Embodiment 3 | 208 | 8 | 57 | 10 | Not |
| Embodiment 4 | 210 | 10 | 71 | 5 | Not |
| Embodiment 5 | 211 | 11 | 79 | 5 | Not |
| Embodiment 6 | 212 | 12 | 86 | 5 | Not |
| Comparative Examples 7 | 213 | 13 | 93 | 5 | Observe |
| Comparative Examples 8 | 210 | 10 | 71 | 75 | Not |
| Comparative Examples 9 | 211 | 11 | 79 | 75 | Observe |
Table 2
Annotate: " thickening " refers to the front portion corresponding to muscle on the back side.
| The degree of depth of indenture (μ m) | Glossiness (%) | The gloss uniformity | ||
| Thickening * | Around the thickening | |||
| Embodiment 7 | 8 | 98 | 97 | ○ |
| Reference example | 10 | 35 | 31 | △ |
| Comparative Examples 10 | 75 | 43 | 28 | × |
| Embodiment 8 | 5 | 95 | 96 | ○ |
Claims (11)
1. the auxiliary resin injection moulding process of a non-resin fluid, be used to produce the molded resin product of high surface finish, this method comprises: (1) but make the fixed die lobe and with the injection molding of the supporting dynamic model lobe of described fixed die lobe, but thereby obtain by the inwall of fixed die lobe and the definite die cavity of inwall of dynamic model lobe, described die cavity communicates with resin inlet and non-resin fluid inlet, and described injection molding is sealed to prevent that the non-resin fluid spills from injection molding when the non-resin fluid injects described die cavity; (2) under the implantation temperature and pressure condition of preliminary election, the resin of fusion form is injected the die cavity of described injection molding, its quantity W by described resin inlet
2Represent with following formula (I): W
2(g)=W
1(g)+Wx (g) is (I) in the formula, W
1By formula W
1=ρ V
1Determine that wherein ρ is the resin density g/cm that measures at normal temperatures and pressures
3, V
1By formula V
1=V
0(1-X) determine, wherein V
0Volume cm for die cavity
3, X is the cubical contraction of resin, described cubical contraction is by formula
Determine, wherein V
aFor under the implantation temperature and pressure condition of described preliminary election, the resin volume cm of the fusion form of predetermined weight
3, V
bVolume cm for the resin of this predetermined weight cured form resin when the cool to room temperature
3, and Wx is determined by formula (II):
Wx=ρ Y (V
0-V
1) (II) ρ is an as above regulation in the formula, Y is 0.3～0.9, V
0And V
1For as above regulation, thereby described die cavity is carried out excessive mold filling, form respectively the molten resin body that first and second apparent surfaces are arranged towards described die cavity opposed inner walls with molten resin; And (3) will be that the pressurization non-resin fluid of inertia is sent in the described die cavity of the described first surface side of molten resin body to described resin, thereby the described second surface of molten resin body is pressed to mould intracavity wall towards described second surface.
2. be 0.5～0.8 according to the Y described in the formula of the process of claim 1 wherein (II).
3. according to the method for claim 1 or 2, this method is used to produce at it has the molded resin product of local ledge corresponding to the first surface side of described molten resin body, and molded resin product is thicker at ledge.
4. according to the method for claim 1 or 2, but wherein one closed chamber is arranged in described dynamic model lobe side away from die cavity, there are an ejector pin support plate and many ejector pins in the sealing chamber, each ejector pin is on but its end reliably is connected to one side at the ejector pin support plate of described dynamic model lobe side, and but the dynamic model lobe has many ejector pin sliding eyes respectively, described many ejector pins wherein are slidingly installed, described closed chamber by each ejector pin sliding eye inwall and each ejector pin of longitudinal extension around between the non-resin fluid passage that forms seal with the die cavity fluid and communicate, and with the pressurization the non-resin fluid source communicate, wherein die cavity is sent into and discharged to described pressurization non-resin fluid by described closed chamber and non-resin fluid passage.
5. according to the method for claim 4, wherein said die cavity also has second import of non-resin fluid.
6. according to the method for claim 1 or 2, first and second surfaces of wherein said molten resin body correspond respectively to the back side and the front of molded resin product.
7. according to the method for claim 1 or 2, wherein said injection molding is made by metal material.
8. according to the method for claim 7, wherein the second surface of described molten resin body is pressed to described mould intracavity wall towards described second surface by the insulation material layer on described mould intracavity wall.
9. method according to Claim 8, wherein said insulation material layer are that the heat-insulating material of 60～0.06W/m.k is made by thermal conductivity factor.
10. according to the method for claim 7, will heat towards the described mould intracavity wall of molten resin body second surface before wherein in step (2), injecting.
11. according to the method for claim 10, wherein heating surface is equal to or higher than such temperature to the temperature of the described mould intracavity wall of molten resin body second surface, be lower than at the elastic modelling quantity of resin under this temperature resin under the room temperature elastic modelling quantity 1/3.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18518594 | 1994-07-15 | ||
| JP185185/94 | 1994-07-15 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1148359A CN1148359A (en) | 1997-04-23 |
| CN1079046C true CN1079046C (en) | 2002-02-13 |
Family
ID=16166342
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN94195100A Expired - Lifetime CN1079046C (en) | 1994-07-15 | 1994-09-02 | Method for non-resin fluid-assisted injection molding of a resin |
Country Status (8)
| Country | Link |
|---|---|
| US (1) | US5730926A (en) |
| EP (1) | EP0771264B1 (en) |
| JP (2) | JP3101943B2 (en) |
| KR (1) | KR0174805B1 (en) |
| CN (1) | CN1079046C (en) |
| DE (1) | DE69411594T2 (en) |
| MY (1) | MY111026A (en) |
| WO (1) | WO1996002379A1 (en) |
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|---|---|---|---|---|
| US5972276A (en) * | 1996-10-04 | 1999-10-26 | Asahi Kasei Kogyo Kabushiki Kaisha | Method for the injection molding of a resin |
| US6164953A (en) * | 1998-03-12 | 2000-12-26 | Patent Holding Company | Method and mold to make plastic articles having reduced surface defects and assembly for use therein |
| US6042361A (en) * | 1998-03-12 | 2000-03-28 | Larry J. Winget | Mold for use in plastic injection molding system and venting pin assembly for use therein |
| US6308929B1 (en) * | 1998-10-22 | 2001-10-30 | Klaus A. Wieder | Mold insert |
| GB2343651A (en) * | 1998-11-10 | 2000-05-17 | Ford Motor Co | Plastics moulding |
| US6367765B1 (en) * | 1999-09-09 | 2002-04-09 | Klaus A. Wieder | Mold vent |
| US6432350B1 (en) * | 2000-06-14 | 2002-08-13 | Incoe Corporation | Fluid compression of injection molded plastic materials |
| JP4108269B2 (en) * | 2000-12-07 | 2008-06-25 | 株式会社リコー | Resin molding apparatus and resin molding method |
| SK12682002A3 (en) * | 2001-01-10 | 2003-07-01 | Grupo Antolin Ingenieria, S. A. | Cooling and counter-pressure method for producing plastic parts by injection |
| IL142657A (en) * | 2001-04-17 | 2013-11-28 | Uri L Zilberman | Acetal resin crowns for children |
| US20100297587A1 (en) * | 2001-04-17 | 2010-11-25 | Uri-Dent Ltd. | Dental crowns |
| BR0208960A (en) * | 2001-04-17 | 2004-09-08 | Uri Dent Ltd | Injection Molded Dental Crown, and, Dental Crowns Mass Production Method |
| US7182892B2 (en) * | 2004-04-30 | 2007-02-27 | Lear Corporation | Gas assisted injection molding with fixed volume gas reservoir and temperature control |
| JP3838372B2 (en) | 2004-06-08 | 2006-10-25 | トヨタ自動車株式会社 | Injection molding method and injection molding apparatus |
| JP4810106B2 (en) * | 2005-02-28 | 2011-11-09 | トヨタ自動車株式会社 | Injection mold |
| JP2006326974A (en) * | 2005-05-25 | 2006-12-07 | Toshiba Corp | Mold assembly |
| CN101511563B (en) * | 2006-09-06 | 2012-10-10 | 普瑞曼聚合物株式会社 | Injection molding metal mold and shaped article |
| DE502007003920D1 (en) * | 2006-12-14 | 2010-07-08 | Sulzer Chemtech Ag | Porous dosing element with coating |
| JP2009214345A (en) * | 2008-03-07 | 2009-09-24 | Asahi Kasei Chemicals Corp | Surface modifying injection molding method and injection molding molded by the same |
| JP5377905B2 (en) * | 2008-08-11 | 2013-12-25 | ポリプラスチックス株式会社 | Mold, molded product evaluation method, and molding condition determination method |
| IT1410977B1 (en) * | 2010-06-14 | 2014-10-03 | Automobili Lamborghini Spa | PROCESS AND DEVICES FOR MANUFACTURING PRODUCTS IN COMPOSITE MATERIALS |
| JP5749065B2 (en) * | 2011-04-22 | 2015-07-15 | 住友重機械工業株式会社 | Injection molding machine and injection molding method |
| JP2013018248A (en) * | 2011-07-14 | 2013-01-31 | Honda Motor Co Ltd | Injection molding die and molding |
| CN104203531B (en) * | 2012-04-06 | 2017-03-08 | 旭硝子株式会社 | The manufacture method of the plate body of the plate body of resin framework and resin framework |
| FR3029446B1 (en) * | 2014-12-05 | 2017-01-13 | Plastic Omnium Cie | MOLD FOR MANUFACTURING A PLASTIC PART COMPRISING A SYSTEM FOR REALIZING ORIFICES IN THE WORKPIECE |
| US10464244B2 (en) | 2017-02-15 | 2019-11-05 | Fca Us Llc | Injection mold for ultra thin wall components |
| CN115572052A (en) * | 2022-10-25 | 2023-01-06 | 昆山国显光电有限公司 | Hot bending jig, hot bending system, hot bending method and cover plate |
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| JP4062125B2 (en) * | 2003-02-26 | 2008-03-19 | セイコーエプソン株式会社 | Print control system, print control apparatus, and print control method |
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| US5458846A (en) * | 1988-12-05 | 1995-10-17 | Carroll; Robert E. | Method of injection molding |
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| JPH0462125A (en) * | 1990-06-27 | 1992-02-27 | Isuzu Motors Ltd | Mold for compressed gas-feeding molding |
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| US5344596A (en) * | 1992-03-23 | 1994-09-06 | Icp Systems, Inc. | Method for fluid compression of injection molded plastic material |
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- 1994-09-02 KR KR1019960706109A patent/KR0174805B1/en not_active IP Right Cessation
- 1994-09-02 US US08/722,104 patent/US5730926A/en not_active Expired - Lifetime
- 1994-09-02 WO PCT/JP1994/001457 patent/WO1996002379A1/en active IP Right Grant
- 1994-09-02 CN CN94195100A patent/CN1079046C/en not_active Expired - Lifetime
- 1994-09-02 DE DE69411594T patent/DE69411594T2/en not_active Expired - Lifetime
- 1994-09-02 EP EP94925622A patent/EP0771264B1/en not_active Expired - Lifetime
- 1994-09-02 JP JP08504874A patent/JP3101943B2/en not_active Expired - Lifetime
- 1994-09-03 MY MYPI94002309A patent/MY111026A/en unknown
-
1998
- 1998-12-28 JP JP37191398A patent/JP3151485B2/en not_active Expired - Fee Related
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5038721A (en) * | 1973-08-08 | 1975-04-10 | ||
| WO1993014918A1 (en) * | 1992-02-01 | 1993-08-05 | Haywood Holdings Limited | Gas-assisted injection moulding method and apparatus |
| JP4062125B2 (en) * | 2003-02-26 | 2008-03-19 | セイコーエプソン株式会社 | Print control system, print control apparatus, and print control method |
Also Published As
| Publication number | Publication date |
|---|---|
| KR970702781A (en) | 1997-06-10 |
| JPH11268083A (en) | 1999-10-05 |
| JP3151485B2 (en) | 2001-04-03 |
| WO1996002379A1 (en) | 1996-02-01 |
| US5730926A (en) | 1998-03-24 |
| DE69411594T2 (en) | 1999-04-15 |
| DE69411594D1 (en) | 1998-08-13 |
| KR0174805B1 (en) | 1999-04-01 |
| EP0771264A1 (en) | 1997-05-07 |
| JP3101943B2 (en) | 2000-10-23 |
| MY111026A (en) | 1999-07-31 |
| CN1148359A (en) | 1997-04-23 |
| JPH10503719A (en) | 1998-04-07 |
| EP0771264B1 (en) | 1998-07-08 |
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